Implement ArrayBuffer.isView function (#3403)

JerryScript-DCO-1.0-Signed-off-by: Roland Takacs r.takacs2@partner.samsung.com

jerry-core/api/jerry.c

@@ -3743,15 +3743,7 @@ jerry_value_is_dataview (const jerry_value_t value) /**< value to check if it is
   jerry_assert_api_available ();
 
 #if ENABLED (JERRY_ES2015_BUILTIN_DATAVIEW)
-  if (!ecma_is_value_object (value))
-  {
-    return false;
-  }
-
-  ecma_dataview_object_t *dataview_object_p = (ecma_dataview_object_t *) ecma_get_object_from_value (value);
-
-  return (ecma_get_object_type (&dataview_object_p->header.object) == ECMA_OBJECT_TYPE_CLASS
-          && dataview_object_p->header.u.class_prop.class_id == LIT_MAGIC_STRING_DATAVIEW_UL);
+  return ecma_is_dataview (value);
 #else /* !ENABLED (JERRY_ES2015_BUILTIN_DATAVIEW) */
   JERRY_UNUSED (value);
   return false;

jerry-core/ecma/builtin-objects/ecma-builtin-arraybuffer.c

@@ -19,7 +19,9 @@
 #include "ecma-globals.h"
 #include "ecma-helpers.h"
 #include "ecma-arraybuffer-object.h"
+#include "ecma-dataview-object.h"
 #include "ecma-try-catch-macro.h"
+#include "ecma-typedarray-object.h"
 #include "jrt.h"
 
 #if ENABLED (JERRY_ES2015_BUILTIN_TYPEDARRAY)
@@ -55,11 +57,8 @@ ecma_builtin_arraybuffer_object_is_view (ecma_value_t this_arg, /**< 'this' argu
                                          ecma_value_t arg) /**< argument 1 */
 {
   JERRY_UNUSED (this_arg);
-  JERRY_UNUSED (arg);
 
-  /* TODO: if arg has [[ViewArrayBuffer]], return true */
-
-  return ECMA_VALUE_FALSE;
+  return ecma_make_boolean_value (ecma_is_typedarray (arg) || ecma_is_dataview (arg));
 } /* ecma_builtin_arraybuffer_object_is_view */
 
 /**

jerry-core/ecma/operations/ecma-dataview-object.c

@@ -306,6 +306,26 @@ ecma_op_dataview_get_set_view_value (ecma_value_t view, /**< the operation's 'vi
   return ECMA_VALUE_UNDEFINED;
 } /* ecma_op_dataview_get_set_view_value */
 
+/**
+ * Check if the value is dataview
+ *
+ * @return true - if value is a DataView object
+ *         false - otherwise
+ */
+bool
+ecma_is_dataview (ecma_value_t value) /**< the target need to be checked */
+{
+  if (!ecma_is_value_object (value))
+  {
+    return false;
+  }
+
+  ecma_dataview_object_t *dataview_object_p = (ecma_dataview_object_t *) ecma_get_object_from_value (value);
+
+  return (ecma_get_object_type (&dataview_object_p->header.object) == ECMA_OBJECT_TYPE_CLASS
+          && dataview_object_p->header.u.class_prop.class_id == LIT_MAGIC_STRING_DATAVIEW_UL);
+} /* ecma_is_dataview */
+
 /**
  * @}
  * @}

jerry-core/ecma/operations/ecma-dataview-object.h

@@ -32,6 +32,7 @@ ecma_dataview_object_t *ecma_op_dataview_get_object (ecma_value_t this_arg);
 ecma_value_t ecma_op_dataview_get_set_view_value (ecma_value_t view, ecma_value_t request_index,
                                                   ecma_value_t little_endian, ecma_value_t value_to_set,
                                                   ecma_typedarray_type_t id);
+bool ecma_is_dataview (ecma_value_t value);
 
 /**
  * @}

tests/jerry/es2015/arraybuffer-isview.js

@@ -0,0 +1,37 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+assert(ArrayBuffer.isView() === false);
+assert(ArrayBuffer.isView([]) === false);
+assert(ArrayBuffer.isView({}) === false);
+assert(ArrayBuffer.isView(null) === false);
+assert(ArrayBuffer.isView(undefined) === false);
+assert(ArrayBuffer.isView(new ArrayBuffer(10)) === false);
+
+assert(ArrayBuffer.isView(new Int8Array()) === true);
+assert(ArrayBuffer.isView(new Uint8Array()) === true);
+assert(ArrayBuffer.isView(new Uint8ClampedArray()) === true);
+assert(ArrayBuffer.isView(new Int16Array()) === true);
+assert(ArrayBuffer.isView(new Uint16Array()) === true);
+assert(ArrayBuffer.isView(new Int32Array()) === true);
+assert(ArrayBuffer.isView(new Uint32Array()) === true);
+assert(ArrayBuffer.isView(new Float32Array()) === true);
+assert(ArrayBuffer.isView(new Float64Array()) === true);
+
+assert(ArrayBuffer.isView(new Int8Array(10).subarray(0, 3)) === true);
+
+var buffer = new ArrayBuffer(2);
+var dv = new DataView(buffer);
+assert(ArrayBuffer.isView(dv) === true);